Mobile data communications is rapidly becoming one of the fastest growing segments of the mobile communications market. A strong driving force is the fast growing portable computing market and the need for flexible wireless data communications it creates. This market force is further emphasized by the smaller, more personal oriented computing devices, such as Personal Digital Assistants (PDAs), and other so called palm top computing devices. With PDAs and other such personal computing devices, as well as with more conventional portable computers, it is possible to send and receive electronic mail, facsimiles, and even browse public information networks such as the world wide web. As these activities become popular for mobile equipment users, so too will the demand for mobile wireless data services.
At the same time, other types of mobile communications services are also in increased demand. These other services include mobile telephone interconnect service, such as cellular telephone, and dispatch radio service, for example. Typically these types of services are provided with separate equipment. That is, traditionally, dispatch and telephone interconnect systems have been separate systems, each requiring fixed and mobile equipment. However, there has been a move underway to provide multiple communications services to mobile users using common mobile and fixed equipment. These are the so called integrated services radio networks, an excellent example of which is found in U.S. Pat. No. 5,548,631 to Krebs et al. These systems use digital modulation for the radio channel, and are typically time divisioned to allow multiple channels on a single frequency or pair of frequencies.
Mobile data service, or packet data, as it is sometimes referred, has been added to cellular telephone service such as GSM. An example of which can be found in U.S. Pat. No. 5,590,133 to Billstrom et al. However, to date, packet data service has not been made available commercially in integrated services radio networks. In doing so, a number of problems are presented, and chief among these is the registration of mobile subscriber units or mobile stations for packet data service.
In a typical communications equipment network a subscriber data base is maintained that includes provisioning information, feature activation status, and so forth This database is typically referred to as a home location register (HLR), and is well understood. Upon receiving a request for registration from a mobile station, the network equipment will access the HLR, find the correlating subscriber record, and determine what features to activate for the mobile station, as well as the necessary authentication information, among other pertinent information. This information is transferred to another database called the visit location register (VLR), which is also well understood in the art. The VLR is used by the system to also track the location in the system of the mobile station. That is, what particular cell or cells the mobile station was most recently in, so that an incoming call may be routed correctly.
In adding any service such as packet data service to a communications network, a VLR function is also necessary to track mobile stations within the serving area. This will allow the system to, for example, send notifiers that the system has received email for the mobile station. Therefore, there is a need, in an integrated services radio system, for a means by which a mobile station can register for packet data service, and for a means by which the serving equipment can track the mobile station.